Swap out TOTP library

database/init.sql

@@ -35,6 +35,7 @@ CREATE TABLE IF NOT EXISTS client_store
 CREATE TABLE IF NOT EXISTS otp
 (
     subject TEXT PRIMARY KEY UNIQUE NOT NULL,
-    raw     BLOB                    NOT NULL,
+    secret  TEXT                    NOT NULL,
+    digits  INTEGER                 NOT NULL,
     FOREIGN KEY (subject) REFERENCES users (subject)
 );

database/tx.go

@@ -4,7 +4,6 @@ import (
 	"database/sql"
 	"fmt"
 	"github.com/1f349/tulip/password"
-	"github.com/1f349/twofactor"
 	"github.com/go-oauth2/oauth2/v4"
 	"github.com/google/uuid"
 	"time"
@@ -167,23 +166,20 @@ WHERE subject = ?`,
 	return nil
 }
 
-func (t *Tx) SetTwoFactor(sub uuid.UUID, totp *twofactor.Totp) error {
+func (t *Tx) SetTwoFactor(sub uuid.UUID, secret string, digits int) error {
-	u, err := totp.ToBytes()
+	_, err := t.tx.Exec(`INSERT INTO otp(subject, secret, digits) VALUES (?, ?, ?) ON CONFLICT(subject) DO UPDATE SET secret = excluded.secret, digits = excluded.digits`, sub.String(), secret, digits)
-	if err != nil {
-		return err
-	}
-	_, err = t.tx.Exec(`INSERT INTO otp(subject, raw) VALUES (?, ?) ON CONFLICT(subject) DO UPDATE SET raw = excluded.raw`, sub.String(), u)
 	return err
 }
 
-func (t *Tx) GetTwoFactor(sub uuid.UUID, issuer string) (*twofactor.Totp, error) {
+func (t *Tx) GetTwoFactor(sub uuid.UUID) (string, int, error) {
-	var u []byte
+	var secret string
-	row := t.tx.QueryRow(`SELECT raw FROM otp WHERE subject = ?`, sub.String())
+	var digits int
-	err := row.Scan(&u)
+	row := t.tx.QueryRow(`SELECT secret, digits FROM otp WHERE subject = ?`, sub.String())
+	err := row.Scan(&secret, &digits)
 	if err != nil {
-		return nil, err
+		return "", 0, err
 	}
-	return twofactor.TOTPFromBytes(u, issuer)
+	return secret, digits, nil
 }
 
 func (t *Tx) HasTwoFactor(sub uuid.UUID) (bool, error) {

go.mod

@@ -5,7 +5,6 @@ go 1.21.1
 require (
 	github.com/1f349/cache v0.0.2
 	github.com/1f349/overlapfs v0.0.1
-	github.com/1f349/twofactor v1.0.4
 	github.com/1f349/violet v0.0.9
 	github.com/MrMelon54/exit-reload v0.0.1
 	github.com/MrMelon54/pronouns v1.0.1
@@ -18,7 +17,9 @@ require (
 	github.com/google/uuid v1.3.1
 	github.com/julienschmidt/httprouter v1.3.0
 	github.com/mattn/go-sqlite3 v1.14.17
+	github.com/skip2/go-qrcode v0.0.0-20200617195104-da1b6568686e
 	github.com/stretchr/testify v1.8.4
+	github.com/xlzd/gotp v0.1.0
 	golang.org/x/crypto v0.13.0
 	golang.org/x/text v0.13.0
 )
@@ -29,9 +30,6 @@ require (
 	github.com/emersion/go-textwrapper v0.0.0-20200911093747-65d896831594 // indirect
 	github.com/golang-jwt/jwt v3.2.2+incompatible // indirect
 	github.com/pmezard/go-difflib v1.0.0 // indirect
-	github.com/sec51/convert v1.0.2 // indirect
-	github.com/sec51/gf256 v0.0.0-20160126143050-2454accbeb9e // indirect
-	github.com/sec51/qrcode v0.0.0-20160126144534-b7779abbcaf1 // indirect
 	github.com/tidwall/btree v1.6.0 // indirect
 	github.com/tidwall/buntdb v1.3.0 // indirect
 	github.com/tidwall/gjson v1.16.0 // indirect

go.sum

@@ -3,8 +3,6 @@ github.com/1f349/cache v0.0.2 h1:27QD6zPd9xYyvh9V1qqWq+EAt5+N+qvyGWKfnjMrhP8=
 github.com/1f349/cache v0.0.2/go.mod h1:LibAMy13dF0KO1fQA9aEjZPBCB6Y4b5kKYEQJUqc2rQ=
 github.com/1f349/overlapfs v0.0.1 h1:LAxBolrXFAgU0yqZtXg/C/aaPq3eoQSPpBc49BHuTp0=
 github.com/1f349/overlapfs v0.0.1/go.mod h1:I6aItQycr7nrzplmfNXp/QF9tTmKRSgY3fXmu/7Ky2o=
-github.com/1f349/twofactor v1.0.4 h1:kN4EEGFlKRa7fGrxS+FpgwJI+tllES6YzXqCqurk4Uk=
-github.com/1f349/twofactor v1.0.4/go.mod h1:gnG80vElwqLWNMnLT57yu4o4L1GdXGPP6pcIPlapXZs=
 github.com/1f349/violet v0.0.9 h1:eQfc5fDMKJXVFUjS2UiAGTkOVVBamppD5dguhmU4GeU=
 github.com/1f349/violet v0.0.9/go.mod h1:Uzu6I1pLBP5UEzcUCTQBbk/NTfI5TAABSrowa8DSpR0=
 github.com/MrMelon54/exit-reload v0.0.1 h1:sxHa59tNEQMcikwuX2+93lw6Vi1+R7oCRF8a0C3alXc=
@@ -96,14 +94,10 @@ github.com/onsi/gomega v1.10.1/go.mod h1:iN09h71vgCQne3DLsj+A5owkum+a2tYe+TOCB1y
 github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
 github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
 github.com/sclevine/agouti v3.0.0+incompatible/go.mod h1:b4WX9W9L1sfQKXeJf1mUTLZKJ48R1S7H23Ji7oFO5Bw=
-github.com/sec51/convert v1.0.2 h1:NoKWIRARjM3rQglNypMpcXSLLqPsN/uTTzaGeqDKbeg=
-github.com/sec51/convert v1.0.2/go.mod h1:5qL/cT/oiOIvWXy2SccQ7LnacYftqqy9wdyFkTc1k2w=
-github.com/sec51/gf256 v0.0.0-20160126143050-2454accbeb9e h1:wKXba8dfsFjbxkMpzZBKt8gkJAMSm1fIf1OSWQFQrVA=
-github.com/sec51/gf256 v0.0.0-20160126143050-2454accbeb9e/go.mod h1:hCjOqSOB9PBw5MdJ+0uSLCBV7FbLy0xwOR+c193HkcE=
-github.com/sec51/qrcode v0.0.0-20160126144534-b7779abbcaf1 h1:CI9zS8HvMiibvXM/F3IthY797GW77fNYgioJl/8Xzzk=
-github.com/sec51/qrcode v0.0.0-20160126144534-b7779abbcaf1/go.mod h1:uPm44Rj3uXSSOvmKmoeRuAUNUgwH2JHW5KIzqFFS/j4=
 github.com/sergi/go-diff v1.1.0 h1:we8PVUC3FE2uYfodKH/nBHMSetSfHDR6scGdBi+erh0=
 github.com/sergi/go-diff v1.1.0/go.mod h1:STckp+ISIX8hZLjrqAeVduY0gWCT9IjLuqbuNXdaHfM=
+github.com/skip2/go-qrcode v0.0.0-20200617195104-da1b6568686e h1:MRM5ITcdelLK2j1vwZ3Je0FKVCfqOLp5zO6trqMLYs0=
+github.com/skip2/go-qrcode v0.0.0-20200617195104-da1b6568686e/go.mod h1:XV66xRDqSt+GTGFMVlhk3ULuV0y9ZmzeVGR4mloJI3M=
 github.com/smartystreets/assertions v0.0.0-20180927180507-b2de0cb4f26d h1:zE9ykElWQ6/NYmHa3jpm/yHnI4xSofP+UP6SpjHcSeM=
 github.com/smartystreets/assertions v0.0.0-20180927180507-b2de0cb4f26d/go.mod h1:OnSkiWE9lh6wB0YB77sQom3nweQdgAjqCqsofrRNTgc=
 github.com/smartystreets/goconvey v1.6.4 h1:fv0U8FUIMPNf1L9lnHLvLhgicrIVChEkdzIKYqbNC9s=
@@ -155,6 +149,8 @@ github.com/xeipuuv/gojsonreference v0.0.0-20180127040603-bd5ef7bd5415 h1:EzJWgHo
 github.com/xeipuuv/gojsonreference v0.0.0-20180127040603-bd5ef7bd5415/go.mod h1:GwrjFmJcFw6At/Gs6z4yjiIwzuJ1/+UwLxMQDVQXShQ=
 github.com/xeipuuv/gojsonschema v1.2.0 h1:LhYJRs+L4fBtjZUfuSZIKGeVu0QRy8e5Xi7D17UxZ74=
 github.com/xeipuuv/gojsonschema v1.2.0/go.mod h1:anYRn/JVcOK2ZgGU+IjEV4nwlhoK5sQluxsYJ78Id3Y=
+github.com/xlzd/gotp v0.1.0 h1:37blvlKCh38s+fkem+fFh7sMnceltoIEBYTVXyoa5Po=
+github.com/xlzd/gotp v0.1.0/go.mod h1:ndLJ3JKzi3xLmUProq4LLxCuECL93dG9WASNLpHz8qg=
 github.com/yalp/jsonpath v0.0.0-20180802001716-5cc68e5049a0 h1:6fRhSjgLCkTD3JnJxvaJ4Sj+TYblw757bqYgZaOq5ZY=
 github.com/yalp/jsonpath v0.0.0-20180802001716-5cc68e5049a0/go.mod h1:/LWChgwKmvncFJFHJ7Gvn9wZArjbV5/FppcK2fKk/tI=
 github.com/yudai/gojsondiff v1.0.0 h1:27cbfqXLVEJ1o8I6v3y9lg8Ydm53EKqHXAOMxEGlCOA=

pages/edit-otp.go.html

@@ -9,6 +9,8 @@
 </header>
 <main>
     <form method="POST" action="/edit/otp">
+        <input type="hidden" name="secret" value="{{.OtpSecret}}"/>
+        <input type="hidden" name="digits" value="{{.OtpDigits}}"/>
         <p>
             <img src="{{.OtpQr}}" style="width:{{.QrWidth}}px" alt="OTP QR code not loading"/>
         </p>

server/otp.go

@@ -2,17 +2,17 @@ package server
 
 import (
 	"bytes"
-	"crypto"
 	"encoding/base64"
 	"github.com/1f349/tulip/database"
 	"github.com/1f349/tulip/pages"
-	"github.com/1f349/twofactor"
 	"github.com/google/uuid"
 	"github.com/julienschmidt/httprouter"
+	"github.com/skip2/go-qrcode"
+	"github.com/xlzd/gotp"
 	"html/template"
 	"image/png"
-	"log"
 	"net/http"
+	"time"
 )
 
 func (h *HttpServer) LoginOtpGet(rw http.ResponseWriter, req *http.Request, _ httprouter.Params, auth UserAuth) {
@@ -49,14 +49,15 @@ func (h *HttpServer) LoginOtpPost(rw http.ResponseWriter, req *http.Request, _ h
 
 func (h *HttpServer) fetchAndValidateOtp(rw http.ResponseWriter, sub uuid.UUID, code string) bool {
 	var hasOtp bool
-	var otp *twofactor.Totp
+	var secret string
+	var digits int
 	if h.DbTx(rw, func(tx *database.Tx) (err error) {
 		hasOtp, err = tx.HasTwoFactor(sub)
 		if err != nil {
 			return
 		}
 		if hasOtp {
-			otp, err = tx.GetTwoFactor(sub, h.conf.OtpIssuer)
+			secret, digits, err = tx.GetTwoFactor(sub)
 		}
 		return
 	}) {
@@ -64,14 +65,8 @@ func (h *HttpServer) fetchAndValidateOtp(rw http.ResponseWriter, sub uuid.UUID,
 	}
 
 	if hasOtp {
-		defer func() {
+		totp := gotp.NewTOTP(secret, digits, 30, nil)
-			h.DbTx(rw, func(tx *database.Tx) error {
+		if !verifyTotp(totp, code) {
-				return tx.SetTwoFactor(sub, otp)
-			})
-		}()
-
-		err := otp.Validate(code)
-		if err != nil {
 			http.Error(rw, "400 Bad Request: Invalid OTP code", http.StatusBadRequest)
 			return true
 		}
@@ -81,7 +76,7 @@ func (h *HttpServer) fetchAndValidateOtp(rw http.ResponseWriter, sub uuid.UUID,
 }
 
 func (h *HttpServer) EditOtpGet(rw http.ResponseWriter, req *http.Request, _ httprouter.Params, auth UserAuth) {
-	var digits = 0
+	var digits int
 	switch req.URL.Query().Get("digits") {
 	case "6":
 		digits = 6
@@ -94,24 +89,6 @@ func (h *HttpServer) EditOtpGet(rw http.ResponseWriter, req *http.Request, _ htt
 		return
 	}
 
-	var otp *twofactor.Totp
-
-	otpRaw, ok := auth.Session.Get("temp-otp")
-	if ok {
-		if otp, ok = otpRaw.(*twofactor.Totp); !ok {
-			http.Error(rw, "400 Bad Request: invalid session, try clearing your cookies", http.StatusBadRequest)
-			return
-		}
-
-		// check OTP code matches number of digits
-		tempCode, err := otp.OTP()
-		if err != nil || len(tempCode) != digits {
-			otp = nil
-		}
-	}
-
-	// make a new otp handler if needed
-	if otp == nil {
 	// get user email
 	var email string
 	if h.DbTx(rw, func(tx *database.Tx) error {
@@ -122,74 +99,76 @@ func (h *HttpServer) EditOtpGet(rw http.ResponseWriter, req *http.Request, _ htt
 		return
 	}
 
-		// generate OTP key
+	secret := gotp.RandomSecret(64)
-		var err error
+	if secret == "" {
-		otp, err = twofactor.NewTOTP(email, h.conf.OtpIssuer, crypto.SHA512, digits)
+		http.Error(rw, "500 Internal Server Error: failed to generate OTP secret", http.StatusInternalServerError)
-		if err != nil {
-			http.Error(rw, "500 Internal Server Error: Failed to generate OTP key", http.StatusInternalServerError)
 		return
 	}
+	totp := gotp.NewTOTP(secret, digits, 30, nil)
+	otpUri := totp.ProvisioningUri(email, h.conf.OtpIssuer)
+	code, err := qrcode.New(otpUri, qrcode.Medium)
+	if err != nil {
+		http.Error(rw, "500 Internal Server Error: failed to generate QR code", http.StatusInternalServerError)
+		return
+	}
+	qrImg := code.Image(60 * 4)
+	qrBounds := qrImg.Bounds()
+	qrWidth := qrBounds.Dx()
 
-		// save otp key
+	qrBuf := new(bytes.Buffer)
-		auth.Session.Set("temp-otp", otp)
+	if png.Encode(qrBuf, qrImg) != nil {
-		err = auth.Session.Save()
+		http.Error(rw, "500 Internal Server Error: failed to generate PNG image of QR code", http.StatusInternalServerError)
-		if err != nil {
-			http.Error(rw, "500 Internal Server Error: Failed to save session", http.StatusInternalServerError)
-			return
-		}
-	}
-
-	// get qr and url
-	otpQr, err := otp.QR()
-	if err != nil {
-		http.Error(rw, "500 Internal Server Error: Failed to generate OTP QR code", http.StatusInternalServerError)
-		return
-	}
-	decode, err := png.Decode(bytes.NewReader(otpQr))
-	if err != nil {
-		return
-	}
-	b := decode.Bounds()
-	qrWidth := b.Dx() / 4
-	otpUrl, err := otp.URL()
-	if err != nil {
-		http.Error(rw, "500 Internal Server Error: Failed to generate OTP URL", http.StatusInternalServerError)
 		return
 	}
 
 	// render page
 	pages.RenderPageTemplate(rw, "edit-otp", map[string]any{
 		"ServiceName": h.conf.ServiceName,
-		"OtpQr":       template.URL("data:image/png;base64," + base64.StdEncoding.EncodeToString(otpQr)),
+		"OtpQr":       template.URL("data:qrImg/png;base64," + base64.StdEncoding.EncodeToString(qrBuf.Bytes())),
 		"QrWidth":     qrWidth,
-		"OtpUrl":      otpUrl,
+		"OtpUrl":      otpUri,
+		"OtpSecret":   secret,
+		"OtpDigits":   digits,
 	})
 }
 
 func (h *HttpServer) EditOtpPost(rw http.ResponseWriter, req *http.Request, _ httprouter.Params, auth UserAuth) {
-	var otp *twofactor.Totp
+	var digits int
-
+	switch req.FormValue("digits") {
-	otpRaw, ok := auth.Session.Get("temp-otp")
+	case "6":
-	if !ok {
+		digits = 6
-		http.Error(rw, "400 Bad Request: invalid session, try clearing your cookies", http.StatusBadRequest)
+	case "7":
-		return
+		digits = 7
-	}
+	case "8":
-	if otp, ok = otpRaw.(*twofactor.Totp); !ok {
+		digits = 8
-		http.Error(rw, "400 Bad Request: invalid session, try clearing your cookies", http.StatusBadRequest)
+	default:
-		return
+		http.Error(rw, "400 Bad Request: Invalid number of digits for OTP code", http.StatusBadRequest)
-	}
-	err := otp.Validate(req.FormValue("code"))
-	if err != nil {
-		http.Error(rw, "400 Bad Request: invalid OTP code: "+err.Error(), http.StatusBadRequest)
-		log.Println()
 		return
 	}
 
-	if h.DbTx(rw, func(tx *database.Tx) error {
+	secret := req.FormValue("secret")
-		return tx.SetTwoFactor(auth.Data.ID, otp)
+	if !gotp.IsSecretValid(secret) {
-	}) {
+		http.Error(rw, "400 Bad Request: Invalid secret", http.StatusBadRequest)
+		return
+	}
+
+	totp := gotp.NewTOTP(secret, digits, 30, nil)
+
+	if !verifyTotp(totp, req.FormValue("code")) {
+		http.Error(rw, "400 Bad Request: invalid OTP code", http.StatusBadRequest)
 		return
 	}
 
 	http.Redirect(rw, req, "/", http.StatusFound)
 }
+
+func verifyTotp(totp *gotp.TOTP, code string) bool {
+	t := time.Now()
+	if totp.VerifyTime(code, t) {
+		return true
+	}
+	if totp.VerifyTime(code, t.Add(-30*time.Second)) {
+		return true
+	}
+	return totp.VerifyTime(code, t.Add(30*time.Second))
+}